You still haven't given me a start date for your MWP. I've found a lot of disagreement, dates as early as 800AD and as late as 1050AD. Hard to suggest possible causes for something when you don't know when it starts.

Nov 1, 2017 at 11:49 PM | Entropic man

So is that why Mann just erased it? Now you are claiming an end date for something Climate Science has denied existed, and trying to shift responsibility onto me and others for proving when it started, even though William M Connolley has been busy on Wikipedia etc trying to support Mann.

Shouldn't Climate Science just revert back to Hubert Lamb's approximation of climate history, which was originally acceptable to the IPCC?

Surely you learned or taught (?) at school about climate variation? When did you decide there was no MWP, and support Mann, yet now you accept there was an MWP, which does not support Mann?

It is better in Science to adjust your science assumptions, rather than data. Will Mann admit fault and be called as an expert witness against himself?

If no-one can agree on when it started, when it it ended or what the temperature was, did the MWP exist at all?

Nov 2, 2017 at 12:24 AM | Entropic man

Why were you claiming when it ended, if it didn't exist?

You are adjusting your position, are you ready to reject the Hockey Stick and try again?

EM you have just given a minimum and maximum length of this much discussed period, thank you.

Steve richards, here is Entropic Man from Bishop Hill 2013

"http://thinkprogress.org/wp-content/uploads/2013/07/Mann-Order-CEI-1.pdf

The DC Superior Court upholds Michael Mann's right to proceed in his defamation suit against National Review and CEI.

It also allows discovery in the plaintiffs' records. Here's a chance to study the denier MO.

Jul 21, 2013 at 7:19 PM | Entropic Man"

As it was Mann who got rid of the MWP, that Entropic Man has now agreed did exist, started (date unknown) and finished (date possibly known), there is clear evidence of the MO of those within Climate Science denying rather a lot, then and now.

Will the IPCC formally retract its previous dependence on Mann's Hockey Stick, and apologise to those who have suffered the consequences of Climate Science's distortion of facts to suit their cause?

"Run the model over a time period of 11 days with a fine grid updated every few minutes. Reset the system with a data dump of new observations.every six hours. You are forecasting weather.

Run the model over a time period of 50 years with a coarser grid updated every few hours. Forcings are randomised or from an RCP. You are forecasting climate."

Hi EM you are confirming rhoda's big concern. I totally agree that you can change the resolution of the model and include/discard elements that you don't think are necessary. So in climate modelling mode (Climate is the average of the weather by definition) you include the CO2 parameterisation but increase the timestep so you are no longer modelling weather, so presumably parameterise that too in some way.

Do you not see a problem in modelling climate by discounting the weather you are supposed to be modelling? I assume rhoda's concern is the new CO2 effect you added will now warm the surface via back radiation or whatever but have now removed the ability to model convection properly that would possibly dump this new found heat in the upper troposphere or the stratosphere.

Conversely a weather model will ignore things like CO2 and also many stability factors that a climate model will need. GCMs are inherently unstable so for example your weather model may warm spuriously by a degree a week which is fine in this case. In a hundred year run though by the end Earth will be about the temperature of the surface if the sun which is probably not ideal if you are looking at the effect the CO2 has. Therefore this is one of many damping effects that may be applied. GCMs do not conserve energy so a common problem as well as all the numerical instability in the models that need friction like damping to stop the models blowing up. A historical example is 'flux correction' where the equator got too hot and the poles too cold. There literally was a hard coded energy movement towards the poles to fix this. Nowadays there are loads of smaller parameters and ocean models to achieve the same movement of energy. It is probably pretty simple to tweak these to get the values that you want in your model run.

Do you not have concerns that GCMs which are great for weather forecasting and a myriad of useful controlled experiments are being misused for something that they aren't even built to be able manage. The climate examples are so circular in how the are used to get the results that are desired.

Scientists think that the temperature in Europe in 1540 exceeded the temperatures we see today.

http://iopscience.iop.org/article/10.1088/1748-9326/11/11/114021/meta

There is no evidence that AGW has taken place this century. True or false?

SC, True, there is no evidence of AGW.

The Climate, like daily, seasonal and annual weather continues to vary. Weather variations are better understood, and are the subject of daily observations and comment by the public. Climate variations are no better understood now, than they were 20+ years ago, due to CO2 AGW Fixation by Climate Scientists.

You still haven't given me a start date for your MWP. I've found a lot of disagreement, dates as early as 800AD and as late as 1050AD. Hard to suggest possible causes for something when you don't know when it starts.

Nov 1, 2017 at 11:49 PM | Entropic man

You still haven't given dates or Minutes of the meetings when it was decided that CO2 was the Planet's Temperature Control Knob, that the MWP and LIA did not exist, that Climate Science had been settled, and that Climate Scientists were experts in statistics.

It is hard to suggest possible causes for the lack of evidence provided by Climate Scientists, they have had enough time and money.

If there was an explanation for the LIA and MWP at last, that would be an achievement. However, Climate Science logically REQUIRES that such an explanation must be in place before any claim that the Detection and Attribution problem is solved so as to put the blame (or give the credit) for warming on CO2. No reliable D & A means no plausible CAGW.

We, and I mean all of us on both sides, don't know the mechanisms or limits of 'natural variation'.

Nov 2, 2017 at 3:00 PM | rhoda

..... hence Mann did away with the Inconvenient Truth of Climate History, and Flatlined the shaft of his Hockey Stick.

Entropic Man has confirmed that Mann was wrong about the MWP.

If only Climate Science Peer Reviewers had spotted the obvious/deliberate mistake, before allowing the IPCC to publish it around the World. Now they are stuck with a stick with a straight shaft, that needs to be shoved somewhere short of sunshine.

The MWP was unlikely to be caused by a high atmospheric concentration of carbon dioxide. We are also told that the gas remains in the atmosphere for at least 500 years so we would have known about it. (I don’t agree with that figure, by the way.)

Leaving aside changes in orbit, that leaves some sort of solar warming or natural variability. I would guess that multiple ocean oscillations happened to have their warm phases in sync.

H H Lamb investigated the MWP and LIA. I have not studied the report but it seems to give a comprehensive description of the conditions but not much on the causes.

http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.455.9147&rep=rep1&type=pdf

He went on to found the CRU at East Anglia in 1971 and declared that its mission was to study the fundamental natural changes in climate. Sadly, as we know, the team ditched all of that in favour of GHG warming and that fundamental study never got done. This, to my mind, is why we now have climate scientists wondering why we have a pause and why the oceans have started cooling.

All warming in the last 50-60 years is attributed to human activity.

http://www.realclimate.org/index.php/archives/2014/08/ipcc-attribution-statements-redux-a-response-to-judith-curry/

Confirmation that they think that CO2 is the control knob.

This is why I say climate science is broken.

Schrodinger's Cat, read more on Lamb!

http://www.cru.uea.ac.uk/about-cru/hubert-lamb

"Even at Foynes in the west of Ireland Hubert was conscious of the severe winters of 1939-40, 1940-41 and 1941-42 which affected most of Europe, in marked contrast to the predominance of mild winters during the previous 40 years."

"During his five and a half years in Ireland he became aware, too, of the tragic history of the potato famine in the 1840s, a matter to which he would later turn his attention in his book, 'Climate, History and the Modern World'."

"My investigations had shown that beyond reasonable doubt that great volcanic eruptions do affect the weather and climate for several years afterwards, while suspended materials – not only the fine dust, but minute droplets and even gases – thrown up into the atmosphere by the blast are still present."

"The study showed that it was the greatest explosions in the low latitudes between about 30°N and 30°S that most regularly yield products that spread around the world, and that the most regular effect of such eruptions was a weakening of the strength of the global circulation. Whereas an eruption in the middle and high latitudes tended to strengthen the circulation in that hemisphere."

"Hubert recognised, too, that further research was needed into the greenhouse effect, but he didn't abandon an interest in the effects of solar disturbance and its relationship to climatic variations."

"He was well acquainted with the pioneering works of Svante Arrhenius in Sweden, and G.S. Callendar in England, and wrote in 1997 that, 'it is now widely thought that the undoubted warming of the world climate in the twentieth century is attributable to the increased concentration in the atmosphere of so-called greenhouse gases'. However, he always referred back to the instrumental record, and his attitude to greenhouse warming remained guarded."

This extract intrigued me in the context of this thread and volcanoes, as no one seems to be referring to the latitudes of eruptions: "...... and that the most regular effect of such eruptions was a weakening of the strength of the global circulation. Whereas an eruption in the middle and high latitudes tended to strengthen the circulation in that hemisphere."

If only Climate Scientists had learned more about integrity and honesty from HH Lamb. As a Quaker, his motives were honourable and humanitarian.

Schrodinger's Cat, and from Gavin at Real Climate, to Judith Curry at Climate etc

https://judithcurry.com/2014/08/28/atlantic-vs-pacific-vs-agw/

tonyb | August 28, 2014 at 8:18 am |
Judith said;
"I live on planet Earth observations, and Gavin lives on planet climate model. I would appreciate some discussion that points out anything significant in Gavin’s post that refutes my arguments."

"Well Judith, you used to live on ‘planet climate model’ as well, with frequent excursions to ‘planet with very little factual data’. You seem to have caught a rocket to planet sanity, A.k.a Earth.

Perhaps you can remember your escape route from Planet climate model and plot Gavin a course to here, where the real world is carrying on as normal in his absence."

curryja | August 28, 2014 at 8:25 am |
"Interesting point Tony, my research prior to about 2004 was physical process studies motivated by improving climate models (combination of small scale observations, theory, modeling). My research the past decade has been observationally based, spiced with theory (i’ve increasingly abandoned the big climate models)."

Gavin's Real Climate post was all IPCC theory-derived computer model evidence, a self-certified fallacious prophecy, that has unsurprisingly failed the real world.

https://wattsupwiththat.com/2017/11/02/study-u-s-climate-closely-follows-pacific-ocean-cycle-known-as-the-pdo/

"Just as the sun rises and sets each day, thereby modifying our daily diurnal and nocturnal temperature cycles, the oceans also cycle and change on a regular and quite predictable time scale. On a daily, monthly, yearly and decadal scale, the oceans go through periods of warming and cooling on a large scale as the meridional overturning circulation (MOC) does its work transporting the oceans water around the world. Gilbert Walker has been recognized as one of the first to identify these periods of warming and cooling as oscillations, and oscillations that then have a profound effect on the weather trends across the globe, as early as 1908 (D’Aleo & Easterbrook, 2011). It was not until the late 1960s when these oscillations were first found to be statistically significant, and the weather community began to use them to predict and identify worldwide climate trends."

Clever chap Gilbert Walker, didn't need a computer model.

https://en.m.wikipedia.org/wiki/Gilbert_Walker

"Sir Gilbert Thomas Walker, CSI, FRS (14 June 1868 – 4 November 1958) was an English physicist and statistician of the 20th century. Walker studied mathematics and applied it to a variety of fields including aerodynamics, electromagnetism and the analysis of time-series data before taking up a teaching position at Cambridge University. Although he had no experience in meteorology, he was recruited for a post in the Indian Meteorological Department where he worked on statistical approaches to predict the monsoons. He developed the methods in the analysis of time-series data that are now called the Yule-Walker equations. He is known for his groundbreaking description of the Southern Oscillation, a major phenomenon of global climate, and for discovering what is named after him as the Walker circulation, and for greatly advancing the study of climate in general. He was also instrumental in aiding the early career of the Indian mathematical prodigy, Srinivasa Ramanujan."

"Work took me into the Met Office Bracknell in summer 1987, when the new sooper dooper Kray compooter was being installed"

While I was studying the Met Office got their newer Cray T3E I believe. For cimputing reference I had to port the model I was using from the Rutherford Cray YMP8 to the ULCC Convex primarily as the Convex had 1GB if RAM compared to the Cray's 512MB.

SuperJanet between London and Reading was an impressive 8Mb per second though.

Nov 3, 2017 at 12:01 AM | Rob Burton

I was involved with work necessary for the new cooling system for the Met Office's Kray Super Computer and its suite of hall and room space. Which is rather ironic, because refrigeration is not my "thing", and I am pretty hopeless with computers.

Over a number of years, I did have occasional opportunities for practical experience of Isobar heat-to-liquid energy transfer monitoring, both day and night, but my methodology might not be deemed scientific, and some of the data records blurred.

Rob - You made interesting comments about running models for weather compared with climate.a couple of days ago. What is your view of the current state of climate science?

That is a tall order, I know. It is almost impossible to summarise our debate here because of the different views. If I try to summarise my own take on it in a single sentence, I would say this:

Climate scientists, in their obsession with CO2 and its exaggerated warming, underestimate that the oceans contain most of the heat and their oscillations drive most of our weather in the short term and climate in the long term.

Rob Burton &
Nov 3, 2017 at 9:34 AM | Schrodinger's Cat

That is sort of the point I was asking about the teaching of Meteorology v Climate Science at University level.

If the Climate Models are programmed to overheat, and they are based on Meteorological Computer Models, is there damage to Meteorology from irrelevant and damaging adjustments for the purpose of Climate forecasts? The BBC, combined with the Met Office have not helped by trying to hot-up their weather forecasts

http://www.telegraph.co.uk/news/weather/7006815/Met-Office-should-drop-inaccurate-longer-term-forecasts-say-scientists.html

As a country bumpkin and yottie, combined with various work I have done, "weather" both good and bad, has played a significant part of my life. More accurate weather forecasting is something I do appreciate, and would like to see increased/improved further.

I appreciate the skill and confidence of James Stagg
http://www.history.com/news/the-weather-forecast-that-saved-d-day

Nov 3, 2017 at 9:34 AM | Unregistered CommenterSchrodinger's Cat

Cat, I agree totally with what you have been posting. I would "guess" the oceans and the sun provide the variability in the climate. I don't know why anyone would think a GCM is a suitable tool for providing any useful information. Just to add I don't think any of my colleagues during the mid nineties studied anything to do with climate change. That would have been the Met Offices Hadley Centre which was in the Met dept in Reading still.

The joke even then it was originally the Hadley Centre for - Climate Research And Prediction but then had to change it :-)

Nov 3, 2017 at 9:34 AM | Unregistered CommenterSchrodinger's Cat

I have always been most interested in the paleoclimate side and fascinating history of the Earth, though that isn't what I studied. After a few years in IT I decided to catch uo on my science with the brilliant 'sceptic' Magic Universe by Nigel Calder as an asked for christmas present about 2004 I would guess looking at the publication date. That got me looking at the 'controversies' that were going on.

One last point is that work I studied related a lot to what Richard Lindzen did on mid latitude dynamics in the eighties. His papers were great in that he actually wrote in English rather than the technical gobbledegook that a vast number of other authors seem to like to use to obfuscate any actual point that might be trying to make.

I am very much a data person first and applying scientific methodology to it to try and see if it means anything significant.